Like they would ever admit it LOL 
Why not? The viola is a unique and wonderful instrument. Unfortunately there is a tendency to get weak violinists to take up the viola, because the repertoire is slower. You end up with poor violinists playing the viola like a violin that needs more force. I would not call someone like that a real violist.
The viola has some difficult acoustic challenges because its proportions are not ideal. There are particular technical approaches designed to draw out the character of the instrument in both bowing and the left hand. These are all rather recent, with Tertis leading the way followed by Primrose, who has a lot to say about violinists who think they are violists because they dig in harder.
Since there is a real violist in my household who plays the viola as it should be played, and as I probably would not be able to, I can never get the jokes about violists. The music that can be drawn out of this instrument can only be described as powerful-heavenly, and it takes a lot of artistry and technical ability to do so.
If violists have any kind of character trait it would not be unmusicality or stupidity. Perhaps patience and less hubris of the diva for many. In an orchestral or ensemble setting, the viola plays the middle notes. A fine sensitivity to the basses below him, and the sopranos above him, will allow him to bring out the music as a whole to its best advantage. It is the middle note that brings out the flavour and colour of any multi-part work. What personality trait attempts to make others shine, and the group as a whole sound better?
Come to think of it, "bringing out the best" would seem to be the role of the violist, beginning with an instrument that has physical disadvantages to its structure.